Ever since Tom got his first Myspace friend, the rise of social media has been a fascinating development in communication to behold. Search “social media” in Google and you’ll marvel at the nearly 500 million results it returns. From news sites and consulting companies to metrics tracking services and pundits, we are fixated on the great equalizer of the digital age. And rightfully so. One need only follow the conversation around Facebook’s upcoming IPO (which will likely be valued at a jaw dropping $100 billion thanks to its first rank status in ad revenue generation) to realize that social media is more than a tool for conversation – it’s also a powerhouse of commerce.

What began as a way to connect with friends has become a way to forge new friendships, connect with brands, form professional networks, and even organize revolutions. But the latest trend I’m observing in social media seems almost oxymoronic: “antisocial” media.

Take Path, for example. Billed as a personal network rather than a social one, Path allows users to connect and share with a narrow group of friends and family. Limited to only fifty of your closest familiars, this is no place for flippant friending. You can see similar pullbacks in sharing on other platforms as well. Google+ has integrated limited sharing into their platform with Circles, allowing you to share content within specific social circles, e.g., share birth announcements with family, relevant articles with colleagues, and Tebowing pictures with friends (or, more likely, with everyone).

Why are we seeing these private networks develop? I believe it’s because social media sharing has become as natural a form of communicating as phone calls and email, but we don’t always want our “conversations” to be public. Difficult family situations or political opinions are sometimes best kept within a close circle.

The implications of this development for brands are potentially huge. As more consumers limit their level of sharing on social networks, brands will need to work harder than ever to engage an itinerant audience. It will take more than just putting out updates; only curated content and meaningful engagement will earn the attention and trust of consumers.